Database Systems for Efficient Access to Tertiary Memory

摘要

Tertiary storage devices have long been in use for storing massive amounts of data in file-oriented mass storage systems. However, their use in database systems is relatively new. Database systems associate more structure to the data than just raw sequence of bytes. Hence, if they are allowed control of the tertiary memory devices, they can greatly reduce access cost by performing informed caching, query optimization, and query scheduling. However, most conventional database systems are designed for data stored on magnetic disks. Accesses to tertiary storage devices are slow and nonuniform compared to secondary storage devices. Therefore, inclusion of tertiary memory as an active part of the storage hierarchy requires a rethinking of conventional query processing techniques. In this project, our aim is to design a database system that can use its knowledge of the data layout on storage devices to increase the speed of running queries.